Gum base and chewing gum containing edible polyesters and method for manufacture

ABSTRACT

Gum bases and chewing gum formulations, as well as methods for making same, are provided. The gum base and chewing gums include an edible polyester.

RELATED APPLICATIONS

This is a continuation-in-part of PCT patent application PCT/US96/16986,filed on Oct. 22, 1996.

BACKGROUND OF THE INVENTION

The present invention relates generally to chewing gum. Morespecifically the present invention relates to improved formulations forchewing gum and gum bases.

It is of course known to construct chewing gum from a water insolublegum base and a water soluble portion along with flavor(s). Gum base isdesigned to be retained in the mouth throughout the chewing period Thewater soluble portion and flavors are designed to dissipate duringchewing.

Insoluble gum base generally comprises elastomers, resins, fats andoils, softeners, and inorganic fillers. The elastomers can includeeither synthetic elastomers or natural elastomers. Natural elastomersinclude natural rubber. Synthetic elastomers include polyisobutylene,isobutylene-isoprene copolymers, styrene-butadiene copolymers, polyvinylacetate, polyisoprene, polyethylene, vinyl acetate - vinyl lauratecopolymers, and combinations thereof.

It is also known to use in gum base elastomer plasticizers. Suchelastomer plasticizers can include natural rosin esters as well as otherelastomer plasticizers. Additionally, chewing gum base can includefiller/texturizers and softener/emulsifiers. Softeners optimize thechewability and mouth feel of the chewing gum. Softener/emulsifiers thatare typically used include tallow, hydrogenated tallow, hydrogenated andpartially hydrogenated vegetable oils, cocoa butter, glycerolmonostearate, glycerol triacetate, lecithin, and combinations thereof.

In addition to a water insoluble gum base portion, a typical chewing gumcomposition includes a water soluble portion and one or more flavoringagents. The water soluble portion can include bulk sweeteners, highintensity sweeteners, flavoring agents, softeners, emulsifiers, colors,acidulants, fillers, antioxidants, and other components that providedesirable attributes.

SUMMARY OF THE INVENTION

The present invention provides improved chewing gum formulations andbases, as well as methods of producing chewing gum and bases. Pursuantto the present invention chewing gum and gum bases that include ediblepolyesters are provided. In this regard, traditionally used elastomersand elastomer plasticizers can be replaced with edible polyesters.

To this end the present invention provides, in an embodiment, a gum baseincluding at least one edible polyester that is produced through areaction of at least one alcohol chosen from the group consisting ofglycerol, propylene glycol, and 1,3 butylene diol, and at least one acidchosen from the group consisting of citric acid, fumaric acid, adipicacid, malic acid, succinic acid, suberic acid, sebacic acid,dodecanedioic acid, glucaric acid, glutamic acid, glutaric acid, azelaicacid and tartaric acid.

In an embodiment, the base is wax-free.

In an embodiment, the base is non-tacky.

In an embodiment, the base is a bubble gum-type base.

In an embodiment, the edible polyester comprises approximately 1% toabout 80% by weight of the base.

In another embodiment, the present invention provides a gum baseincluding at least approximately 1% by weight of an edible polyesterthat is a product of a condensation reaction of at least one alcoholchosen from the group consisting of trihydroxyl alcohol and dihydroxylalcohol, and at least one acid chosen from the group consisting ofdicarboxylic acid and tricarboxylic acid.

In a further embodiment, the present invention provides a chewing gumformulation comprising an insoluble gum base, a water soluble portion, aflavor, and at least 0.1% by weight of an edible polyester. The ediblepolyester is produced by the reaction of at least one alcohol chosenfrom the group consisting of glycerol, propylene glycol, and 1,3butylene diol and at least one acid chosen from the group consisting ofcitric acid, fumaric acid, adipic acid, malic acid, succinic acid,suberic acid, sebacic acid, dodecanedioic acid, glucaric acid, glutamicacid, glutaric acid, azelaic acid and tartaric acid.

In an embodiment, the formulation includes a bulk sweetener.

In an embodiment, the formulation includes a high intensity sweetener.

In an embodiment, the formulation includes an elastomer plasticizer.

In an embodiment, the formulation includes an elastomer.

In an embodiment, the chewing gum is sugar free.

In yet a still further embodiment, the present invention a method formanufacturing chewing gum comprising the step of adding to a watersoluble portion and a flavor an edible polyester that is produced by thecondensation reaction of at least one alcohol chosen from the groupconsisting of trihydroxyl alcohol and dihydroxyl alcohol and at leastone acid chosen from the group consisting of dicarboxylic acid andtricarboxylic acid.

It is an advantage of the present invention to provide an improved gumbase.

Still further an advantage of the present invention is to provide animproved chewing gum formulation.

Another advantage of the present invention is to provide an improvedmethod for making chewing gum.

Still further an advantage of the present invention is to provide animproved method for making gum base.

Moreover, an advantage of the present invention is that the gum base isbiodegradable.

Furthermore, an advantage of the present invention is to replacetraditional elastomers or elastomer plasticizers in chewing gum baseswith other polymers.

Additional features and advantages of the present invention aredescribed in, and will be apparent from, the detailed description of thepresently preferred embodiments.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

The present invention provides improved chewing gum formulations and gumbase formulations. To this end, the present invention allows for thereplacement or substitution for traditional elastomers and elastomerplasticizers with other polymers specifically edible polyesters.

Polyesters are polymers obtained by the esterification of dicarboxylicacid and dihydroxyl alcohol. Ester linkages may be formed at each end ofeach molecule. Thus, it is possible to build up a large moleculecontaining many ester linkages.

For example, one of the most common polyesters in use is polyethyleneterephthalate made from ethylene glycol and terephthalic acid.Polyethylene terephthalate was developed as a fiber called Dacron. Thispolyester can also be used to make a film having unusual strength.Polyethylene terephthalate is currently used to make PET (polyethyleneterephthalate) plastic bottles used for soft drinks.

In making polyesters, if a trihydroxyl alcohol such as glycerol is used,possible crosslinking occurs. The resultant resinous materials,glyptols, from glycerol and phthalic acid, find applications as coatingsin the lacquer and paint industry.

It is possible to construct polyesters from edible or food gradematerials. To this end, the tri or dihydroxyl alcohols glycerol,propylene glycol, and 1,3-butylene diol can be reacted with tri- ordicarboxylic acids such as citric, fumaric, adipic, malic, succinic, andtartaric acids.

With respect to these alcohols and acids, the reaction of the alcoholand acid form the ester linkages. As the reaction continues extendedpolyester chains are created by a condensation reaction. An initialstudy of various polyesters from these materials by the condensationreaction yielded polyesters that had rubbery, plastic or hard,resin-like textures. Because the starting alcohols and acids are foodgrade materials the resultant product is edible and can be used in foodor confectionary products.

By way of example and not limitation, several polyesters were made usingthe various food acids and glycerol or propylene glycol. Gram quantitieswere made in a test tube heated in an oil bath at about 180°-250° C.from 1/2 hr. to 5 hours to obtain polyesters.

The following polyesters were made:

    ______________________________________                                                        Molar Ratios                                                                  Glycerin                                                                              Propylene Glycol                                      ______________________________________                                        A    Adipic Acid      2\1.28                                                                        --                                            B    Adipic Acid      3.54\1.66                                                                     --                                            C    Adipic Acid      1.4\2.03                                                                      --                                            D    Malic Acid       2.0\1.28                                                                      --                                            E    Malic Acid       --        2\1                                 F    Malic Acid       2\0.5                                                                         --                                            G    Adipic/Malic Acid                                                                              1\1\1.28                                                            --                                            H    Adipic/Malic Acid                                                                              --        1.5\1.5\1                 I    Adipic Acid      --        2\1                                 J    Adipic Acid      --        2\2                                 K    Tartaric Acid    2\1                                                                           --                                            L    Fumaric Acid/Citric Acid                                                                       --        1\1\1                     M    Fumaric Acid     2\1                                                                           --                                            N    Fumaric Acid/Citric Acid                                                                       1\1\1                                                               --                                            O    Adipic Acid      2\1\1**                             P    Adipic Acid      --        2\.1*\2                   Q    Adipic Acid      --        2\.25\1                   R    Adipic Acid      --        2\0.4*\2                  ______________________________________                                         *Low levels of Glycerol added                                                 **Made with Adipic Acid\Glycerin\Propylene Glycol    

Products that were formed were viscous liquids to waxy rubbery-like orplastic gels to hard gels. Generally, as the mixtures were heated,moisture was driven off. Over several hours, liquids turned to gels orif removed from heat became solid gels.

The resultant polyesters were soft to hard plastic and soft to hardrubbery characteristics that had resin like texture. These polyestersappear to be very useful in a gum product. The glycerol adipatepolyester was insoluble in water, chloroform, methanol, isopropylalcohol, 0.1N sodium hydroxide, and concentrated HCl. Other polyesterswere not tested for solubility but are believed to be less than 1%soluble in water.

The compatibility of polyesters with other gum base ingredients can beimproved by increasing the lipophilicity of the polyester. This can beaccomplished by increasing the length of the carbon backbone between thetwo acids of the dicarboxylic acid molecule.

In this regard, adipic acid has a 4 carbon chain between the twocarboxylic acid groups. By increasing the carbon chain between the twogroups to a 6, 8, or 10 carbon chain, lipophilicity can be increased.The 6 carbon chain diacid is suberic acid, and 8 carbon chain diacid issebacic acid, and the I0 carbon chain diacid is dodecanedioic acid.

Other types of naturally occurring diacids may also be used to provide amore lipophilic polyester. Some such diacids include glucaric acid,glutamic acid, glutaric acid, and azelaic acid. Other materials thathave at least two carboxylic acids or alcohol groups can also be used asreactants. Such materials with alcohol or hydroxyl groups are sorbitol,mannitol, glycerol monofatty acids and hydrocolloids.

In addition, low levels of mono carboxylic acids and/or monohydroxylalcohols may be added to the reaction mixture/polyester of dihydroxyl ortricarboxylic alcohol and dicarboxylic or tricarboxylic acids to reactwith any free alcohol or acid groups, respectively. Monohydroxylalcohols such as ethanol, butanol or octanol, or acids such as aceticacid, stearic acid, palmitic acid or other fatty acids may be used.These materials will endcap the polyester to keep it from reacting withother materials, and can also modify the physical properties of thepolyester.

Polyesters can be made by a variety of processes. Besides conventionalmethods of production, polyesters can be made by a condensation reactionin an extruder, by a condensation reaction in a batch process, or may bemade by an enzymatic processes. The process of making the polyester isnot limiting.

The polyesters that can be used pursuant to the present invention arenot limited to linear polyesters, but can also include polyesters thatmay be branched or crosslinked. These may be made with tricarboxylicacids or trihyrdoxyl alcohols. The desired polyester may have a broadrange of physical properties from thick and syrupy to hard and rubberywith thermoplastic properties.

The examples of polyesters set forth below were prepared from adipicacid and glycerin or propylene glycol. Both glycerin and propyleneglycol were predried by heating in a round bottom flask at 50-60° C.under vacuum overnight and stored over a dry helium atmosphere. By wayof example, and not limitation, the following examples were made:

EXAMPLE A

In a 2L cylindrical glass reactor equipped with a mechanical stirrer andheating jacket, 800 g of dried glycerol was charged. A stream of dryhelium was circulated in the reactor and the outlet was connected to atrap maintained in ice-water.

The solution was heated to 100° C. for 90 min. Then 1900g of adipic wascharged into the reactor and the temperature was raised to 150° C. Waterdroplets started condensing. The amount of water condensed is tabulatedbelow as a function of reaction time.

    ______________________________________                                        Time of     Amount of   Extent of                                             Reaction    water condensed                                                                           reaction completed                                    ______________________________________                                         90 min     100 g       21%                                                   150 min     200 g       42%                                                   180 min     250 g       53%                                                   220 min     310 g       66%                                                   240 min     340 g       72.6%\                                      ______________________________________                                    

After 4 hrs the gel point was reached. Two samples were picked out fromthe reactor at 180 min (Sample #A) and 220 min of reaction (Sample #AA)for analysis. The final product (Sample AAA) was recovered from thereactor. It was observed that the product near the walls was more stickythan the product inside the reactor and was kept in a separate jar. Theproduct inside the reactor was foamy.

FTIR spectroscopy analysis of polymer films of samples A and AA cast onKBr windows from chloroform solutions confirmed the polycondensationproducts. Also the amount of water condensed from the reaction indicatedpolyester formation.

EXAMPLE B

In a 3L cylindrical glass reactor equipped with a mechanical stirrer andheating jacket, 700 g (9.19 mole) of dried propylene glycol was charged.A stream of dry helium was circulated in the reactor and the outlet wasconnected to a trap maintained in ice cold water.

The solution was heated to 100° C. for 90 min. Then 1344.5 g (9.19 mole)of adipic acid was charged into the reactor and the temperature wasraised to 150° C. Water droplets started condensing. After two hours thereaction temperature was raised to 180° C. In about 3 hrs. 210 ml ofwater was collected in the trap. The temperature of the reactor wasmaintained at 1 80° C. and vacuum was applied for about 2 hrs. Anadditional 120 ml of water was collected in the trap.

An SEC (Size Exclusion Chromatography) analysis (Sample B) of theproduct indicates the presence of dimers and trimers. The total Mw(Weight Average Molecular Weight) of the product was found to be 2800and (Weight Average Molecular Weight/Number Average MolecularWeight=Polydispersity) Mw/Mn=1.75.

The mechanical stirrer was removed from the reactor and the solution washeated further under vacuum (10⁻³ mm Hg) at 150° C. for 2 hrs; at 180°C. for 2 hrs; and at 200° C. for another 5 hrs. A 15 ml quantity ofcondensate was collected during this period of heating under a vacuum.An SEC analysis of this product (Sample #BB) shows a Mw of 5500 withMw/Mn=1.90.

EXAMPLE C

In a 3L cylindrical glass reactor equipped with a mechanical stirrer andheating jacket, 700 g (9.19 mole) of dried propylene glycol was charged.A stream of dry helium was circulated in the reactor and the outlet wasconnected to a trap maintained in ice cold waters.

The solution was heated to 70° C. for 30 min. Then 1344.5 g (9.19 mole)of adipic acid was charged into the reactor and the temperature wasraised to 100° C. 15 Water droplets started condensing. After one hour 5ml of HCl (0.5 mole %) was added as a catalyst and the reactiontemperature was raised to 150° C. In about 1 hr. 100 ml of water wascollected in the trap. The pH of the collected water was around 4. Thetemperature of the reactor was raised to 180° C. and around 145 ml ofwater was collected in the trap.

An SEC analysis (Sample C) indicates the presence of dimers and trimers.The total Mw of the product was 1700 and Mw/Mn=2.43.

The mechanical stirrer was removed from the reactor. 2.5 ml (0.25 mole%) of HCl was added and the solution was heated further under vacuum(10⁻³ mm Hg) at 220° C. for 4 hrs. A 25 ml quantity of condensate wascollected during this period of heating under vacuum. An SEC analysis ofthis product (Sample #CC) shows the Mw to be 3700 with Mw/Mn=2.47.

As in Example B, size exclusion chromatography (SEC) was carried out ona Varian liquid chromatograph equipped with a refractive detector. ThreeGPC columns from Supelco were used with THF as the eluent. The columnswere calibrated with monodisperse polystyrene standards. The molecularweights and the polydispersity indice were calculated.

EXAMPLE D

In a 3L cylindrical glass reactor equipped with a mechanical stirrer andheating jacket, 313 g (4.11 mole) of dried propylene glycol and 252 g(2.74 mole) of glycerol were charged. A stream of dry helium wascirculated in the reactor and the outlet was connected to a trapmaintained in ice cold water.

The solution was heated to 75° C. for an hour. Then 1200 g (8.22 mole)of adipic acid was charged into the reactor and the temperature of thereactor was kept at 75° C. for 2 hours. The temperature was raised to180° C. and water droplets started condensing. After 2 hours, 140 ml ofwater was collected in the trap. The temperature of the reactor wasincreased to 220° C. and around 90 ml of water was collected in another2 hrs. Vacuum was applied for about 1 hr at 220° C.

The solution became viscous and turned into a gel in about 1 hr. Anadditional 30 ml of water was collected in the trap. The final product(Sample D) was soft, sticky and difficult to remove from the reactor.

EXAMPLE E

In a 3L cylindrical glass reactor equipped with a mechanical stirrer andheating jacket, 468 g (6.15 mole) of dried propylene glycol and 252 g(2.74 mole) of glycerol were charged. A stream of dry helium wascirculated in the reactor and the outlet was connected to a trapmaintained in ice cold water.

The solution was heated to 75° C. for an hour. Then 1500 g (10.26 mole)of adipic acid was charged into the reactor and the temperature was keptat 75° C. for 2 hrs. The temperature was raised to 180° C. and waterdroplets started condensing. After 2 hrs. 140 ml of water was collectedin the trap. The temperature of the reactor was increased to 220° C. andaround 100 ml of water was collected in another 2 hrs. Vacuum wasapplied for about 1 hr at 220° C.

The solution became viscous and a sample was collected after 30 min.(Sample EE). It was fluid-like. The vacuum was applied for another 30min. upon which the solution turned into a gel. An additional 70 ml ofwater was collected in the trap. The reactor was allowed to cool andfinal product was recovered. The product (Sample E) was soft and sticky.

Samples D, E, EE were cross linked and would not dissolve in THF andtherefore were not analyzed by SEC.

In order to determine the amount of initial material remaining a waterwashing of Example E was done. Using a Brabender Plasticorder with a 120ml Sigma mixer bowl and blade, 75.8 g of Example E was mixed with 20 mlof deionized water for 16 minutes. After some swelling another 20 ml ofwater was added and mixed 16 minutes. Then the water extract was removedand more water added. This was repeated 5 more times and the extractsanalyzed for solids content. A total of 1.7% of Example E was extractedindicating very little material remained in the polyester. Polyesterexamples D & E were soaked in deionized water at room temperature forabout I week. The polyesters were removed from the water and dried in avacuum oven overnight at 45 to 50° C.

The following gum bases were made from the 2 washed polyesters using aHaake Rheocord Rheometer and Sigma mixer.

Base Example 1

A 50.0 gram quantity of polyester of Example D was placed in a HaakeRheocord with a Sigma blade mixer. Added to this was 20.0 grams ofcalcium carbonate and blended for 15 minutes at 115° C.

Base Example 2

A 45.0 gram quantity of base of Example 1 above was added to the HaakeRheocord and blended at 115° C. with 20.0 grams of medium molecularweight PV Ac for 15 min.

Base Example 3

A 50.2 gram quantity of polyester of Example E was placed in the HaakeRheocord with the sigma mixer blade. Added to this was 30.0 grams ofcalcium carbonate and blended at 115° C. for 20 minutes.

Base Example 4

A 40.8 gram quantity of base of Example 3 was placed in the HaakeRheocord and blended at 115° C. with 10.0 grams of low molecular weightPV Ac for 10 minutes.

Gum Examples 5, 6, and 7

The following gums were made from bases made above in a BrabenderPlasticorder at 37° C.

    ______________________________________                                                       Ex 5        Ex 6   Ex 7                                        Base Examples  Ex 1        Ex 2   Ex 4                                        ______________________________________                                        Base, grams    18          18     18                                          Sugar, grams   41          41     41                                          45Be Corn Syrup, grams                                                                       11          11     11                                          Peppt. Flavor, grams                                                                         0.7         0.7    0.7                                         Total          70.7        70.7   70.7                                        ______________________________________                                    

Gum evaluation showed Example 5 with polyester and calcium carbonate hada good initial texture but became very soft and tacky in the late chewtexture. Example 6 had a good initial texture as well as a good texturecharacter throughout and was slightly tacky. Example 7 had a goodinitial texture, but became slightly soft and slightly tacky late.

The polyesters made here were not readily compatible with other baseingredients such as elastomers, elastomer plasticizers, waxes, and fats.By using a 2-monoglyceride as the starting diol instead of glycerin orpropylene glycol, it is believed that more compatible polyesters can bedeveloped and used with other gum base ingredients.

It was concluded that a quality chewing gum base and gum product can bemade from polyesters from adipic acid and glycerol and/or propyleneglycol.

By way of further example, a series of samples of polyesters were madeusing the following procedure:

Procedure

The reactants were added to a 2-liter reaction flask having a heatingjacket and equipped with a stirrer, a nitrogen inlet, a nitrogen/vacuumoutlet with a trap, and a thermocouple. The reactants were added to thereaction vessel in the desired molor ratios of alcohol and acid groups(usually stochoimetrically equivalent).

The reaction vessel was purged with nitrogen and heated to 130° C.(sometimes as high as 150° C. to ensure melting of both reactants).After the reactants were melted, the mixture was stirred with amechanical stirrer. The mixture was allowed to react for 2-3 hours.

Water was then collected in the condenser and measured to determine theextent of the reaction. Next, the temperature was raised to 150° C. (ifit was not there already). When water elution slows (usually about anhour), the nitrogen purge was discontinued and the system was run undervacuum. When water elution slowed again (about 1 hour), the temperaturewas raised to 180° C. After the polyester forms a viscous gel (about 70%reaction completion) that stops the mixer (usually about 0.5 to 1 hour),the heat was removed. The polyester was then removed and allowed tocool.

The polyester was then cut into small chunks and placed into a soxhlettube. The polyester was washed with boiling anhydrous ethanol in asoxhlet for about 5 hours to remove low molecular weight polyester(about 10-30% of the original polyester). The "clean" polyester was thendried overnight in a vacuum oven at 40-50° C.

EXAMPLES MADE USING THIS PROCEDURE Example F

A glycerol/adipic acid polyester was made by the above procedure using1408.35 grams of adipic acid and 591.65 grams of glycerol. Thispolyester had good rubbery properties.

Example G

A glycerol/suberic acid polyester was made by the above procedure using1478.82 grams of sebacic acid and 521.18 grams of glycerol. Thispolyester had good rubbery properties.

Example H

A glycerol/sebacic acid polyester was made by the above procedure using1534.27 grams of sebacic acid and 465.73 grams of glycerol. Thispolyester also had good rubbery properties.

Example J

A glycerol/dodecanedioic acid polyester was made by the above procedureusing 1263.24 grams of dodecanedioic acid and 336.76 grams of glycerol.This polyester also had good rubbery properties.

Example K

A 1,3-butanediol/adipic acid polyester was made by the above procedureusing 1280.14 grams of adipic acid and 789.59 grams of 1,3-butanediol.This was a linear polyester that was thick and syrupy, but not asrubbery as the other examples.

During the clean-up extraction process for the above examples, thelonger chain aliphatic diacid polyesters yielded about 10% extractables,whereas the adipic acid/glycerin polyester yielded about 20-30%extractables. This suggests that the longer chain backbone of sebacicacid, suberic acid, or dodecanedioic acid provides polyesters that aremore lipophilic.

Base Example 8

A 28 gram quantity of polyester of Example F, a 28 gram quantity ofpolyester of Example J, and a 14 gram quantity of starch were blended ina Haake Rheocord with a Sigma blade mixer for 10 minutes at 115° C. tomake a chewing gum 10 base.

Base Example 9

A 35 gram quantity of polyester of Example J, 21 gram quantity ofstarch, and a 14 gram quantity of low molecular weight PVAc blended in aHaake Rheocord with a Sigma blade mixer for 10 minutes at 115° C. tomake a chewing gum base.

Base Example 10

A 35 gram quantity of polyester of Example F, 21 gram quantity ofstarch, and a 14 gram quantity of low molecular weight PVAc were blendedin a Haake Rheocord with a Sigma blade mixer for 10 minutes at 115° C.to make a chewing gum base.

Base Example 11

A 35 gram quantity of polyester of Example F, 28 gram quantity ofstarch, and a 7 gram quantity of low molecular weight PVAc were blendedin a Haake Rheocord with a Sigma blade mixer for 10 minutes at 115° C.to make a chewing gum base.

Base Example 12

A 35 gram quantity of polyester of Example J, 21 gram quantity ofstarch, a 7 gram quantity of low molecular weight PVAc, a 3.5 gramquantity hydrogenated cottonseed oil, a 2.1 gram quantity ofhydrogenated soybean oil, and a 1.4 gram quantity of glycerolmonstearate were blended in a Haake Rheocord with a Sigma blade mixerfor 10 minutes at 115° C. to make a chewing gum base.

Base Example 13

When the adipic acid/glycerol polyester of Example F was substituted forExample J in the base formula of Example 12, the composition did notyield a homogeneous mix together. Thus, the longer backbone carbon chaindid improve the lipophilic properties of the polyester.

Gum Examples 14, 15, 16, 17, and 18

Five examples of chewing gum were made with Base Examples 8, 9, 10, 11and 12, respectively, in a Brabender Plasticorder at 37° C. using thefollowing gum formula:

    ______________________________________                                                        %                                                             ______________________________________                                        Base              19.3                                                        Sugar             57.4                                                        Corn Syrup        13.9                                                        Dextrose Monohydrate                                                                            7.3                                                         Glycerin          1.2                                                         Fruit Flavor      0.8                                                         Lecithin          0.1                                                         ______________________________________                                    

Samples of these chewing gums made from these formulas gave good flavorrelease and texture. It was concluded that a quality chewing gum baseand gum product can be made from the polyesters obtained from longerchain hydrocarbon dicarboxylic acids and glycerol.

Chewing gum Examples 16 and 17 were washed with warm tap water to removesolubles and the resulting gum bolus made with Base Examples 10 and 11(glycerol/adipic acid polyester, starch, and low molecular weight PVAc)were tested for biodegradability using an ASTM test method (ASTM D5209).The bolus of Example 10 with 20% PVAc was about equal inbiodegradability to Kraft paper, an accepted standard for comparison.The bolus of Example 11 with 10% PVAc was more biodegradable than Kraftpaper.

Pursuant to the present invention, the polyesters can be used in baseformulations and/or chewing gum formulations. In this regard, thepolyesters can be used as elastomers and/or elastomer plasticizers. Aspart of a gum base, the edible polyesters can comprise approximately 1to about 80% by weight of the gum base. As part of the chewing gum, theedible polyesters can comprise approximately 0.1 to about 70% by weightof the chewing gum.

The polyesters can be used in a variety of different chewing gum andbase formulations.

As previously noted, chewing gum generally consists of a water insolublegum base, a water soluble portion, and flavors.

The insoluble gum base generally comprises elastomers, resins, fats andoils, softeners, and inorganic fillers. The gum base may or may notinclude wax. The insoluble gum base can constitute approximately 5 toabout 95 percent, by weight, of the chewing gum, more commonly, the gumbase comprises 10 to about 50 percent of the gum, and in some preferredembodiments, 20 to about 35 percent, by weight, of the chewing gum.

In an embodiment, the chewing gum base of the present invention containsabout 1% to about 80% weight percent food grade polyester, about 20 toabout 60 weight percent synthetic elastomer, 0 to about 30 weightpercent natural elastomer, about 5 to about 55 weight percent elastomerplasticizer, about 4 to about 35 weight percent filler, about 5 to about35 weight percent softener, and optional minor amounts (about onepercent or less) of miscellaneous ingredients such as colorants,antioxidants, etc.

Synthetic elastomers may include, but are not limited to,polyisobutylene with a GPC weight average molecular weight of about10,000 to about 95,000, isobutylene-isoprene copolymer (butylelastomer), styrene-butadiene copolymers having styrene-butadiene ratiosof about 1:3 to about 3:1, polyvinyl acetate having a GPC weight averagemolecular weight of about 2,000 to about 90,000, polyisoprene,polyethylene, vinyl acetate-vinyl laurate copolymer having vinyl lauratecontent of about 5 to about 50 percent by weight of the copolymer, andcombinations thereof.

Preferred ranges are, for polyisobutylene, 50,000 to 80,000 GPC weightaverage molecular weight, for styrene-butadiene, 1:1 to 1:3 boundstyrene-butadiene, for polyvinyl acetate, 10,000 to 65,000 GPC weightaverage molecular weight with the higher molecular weight polyvinylacetates typically used in bubble gum base, and for vinyl acetate-vinyllaurate, vinyl laurate content of 10-45 percent.

If used, natural elastomers may include natural rubber such as smoked orliquid latex and guayule as well as natural gums such as jelutong, lechicaspi, perillo, sorva, massaranduba balata, massaranduba chocolate,nispero, rosindinha, chicle, gutta hang kang, and combinations thereof.The preferred synthetic elastomer and natural elastomer concentrationsvary depending on whether the chewing gum in which the base is used isadhesive or conventional, bubble gum or regular gum, as discussed below.Preferred natural elastomers include jelutong, chicle, sorva andmassaranduba balata.

If used, elastomer plasticizers may include, but are not limited to,natural rosin esters, often called estergums, such as glycerol esters ofpartially hydrogenated rosin, glycerol esters polymerized rosin,glycerol esters of partially dimerized rosin, glycerol esters of rosin,pentaerythritol esters of partially hydrogenated rosin, methyl andpartially hydrogenated methyl esters of rosin, pentaerythritol esters ofrosin; synthetics such as terpene resins derived from alpha-pinene,beta-pinene, and/or d-limonene; and any suitable combinations of theforegoing, the preferred elastomer plasticizers will also vary dependingon the specific application, and on the type of elastomer which is used.

Fillers/texturizers may include magnesium and calcium carbonate, groundlimestone, silicate types such as magnesium and aluminum silicate, clay,alumina, tale, titanium oxide, mono-, di- and tri-calcium phosphate,cellulose polymers, such as wood, and combinations thereof.

Softeners/emulsifiers may include tallow, hydrogenated tallow,hydrogenated and partially hydrogenated vegetable oils, cocoa butter,glycerol monostearate, glycerol triacetate, lecithin, mono-, di- andtriglycerides, acetylated monoglycerides, fatty acids (e.g. stearic,palmitic, oleic and linoleic acids), and combinations thereof.

Colorants and whiteners may include FD&C-type dyes and lakes, fruit andvegetable extracts, titanium dioxide, and combinations thereof.

The base may or may not include wax. An example of a wax-free gum baseis disclosed in U.S. Pat. No. 5,286,500, the disclosure of which isincorporated herein by reference.

In addition to a water insoluble gum base portion, a typical chewing gumcomposition includes a water soluble bulk portion and one or moreflavoring agents. The water soluble portion can include bulk sweeteners,high intensity sweeteners, flavoring agents, softeners, emulsifiers,colors, acidulants, fillers, antioxidants, and other components thatprovide desired attributes.

The softeners, which are also known as plasticizers and plasticizingagents, generally constitute between approximately 0.5 to about 15% byweight of the chewing gum. The softeners may include glycerin, lecithin,and combinations thereof. Aqueous sweetener solutions such as thosecontaining sorbitol, hydrogenated starch hydrolysates, corn syrup andcombinations thereof, may also be used as softeners and binding agentsin chewing gum.

Bulk sweeteners include both sugar and sugarless components. Bulksweeteners typically constitute 5 to about 95% by weight of the chewinggum, more typically, 20 to 80% by weight, and more commonly, 30 to 60%by weight of the gum.

Sugar sweeteners generally include saccharidc-containing componentscommonly known in the chewing gum art, including, but not limited to,sucrose, dextrose, maltose, dextrin, dried invert sugar, fructose,galactose, corn syrup solids, and the like, alone or in combination.

Sorbitol can be used as a sugarless sweetener. Additionally, sugarlesssweeteners can include, but are not limited to, other sugar alcoholssuch as mannitol, hydrogenated isomoltulose (palatinit), xylitol,hydrogenated starch hydrolysates, maltitol, lactitol and the like, aloneor in combination.

High intensity artificial sweeteners can also be used in combinationwith the above. Preferred sweeteners include, but are not limited tosucralose, aspartame, salts of acesulfame, alitame, saccharin and itssalts, cyclamic acid and its salts, glycyrrhizin, dihydrochalcones,thaumatin, monellin, and the like, alone or in combination. In order toprovide longer lasting sweetness and flavor perception, it may bedesirable to encapsulate or otherwise control the release of at least aportion of the artificial sweetener. Such techniques as wet granulation,wax granulation, spray drying, spray chilling, fluid bed coating,coacervation, and fiber extension may be used to achieve the desiredrelease characteristics.

Usage level of the artificial sweetener will vary greatly and willdepend on such factors as potency of the sweetener, rate of release,desired sweetness of the product, level and type of flavor used and costconsiderations. Thus, the active level of artificial sweetener may varyfrom 0.02 to about 8%. When carriers used for encapsulation areincluded, the usage level of the encapsulated sweetener will beproportionately higher.

Combinations of sugar and/or sugarless sweeteners may be used in chewinggum. Additionally, the softener may also provide additional sweetnesssuch as with aqueous sugar or alditol solutions.

If a low calorie gum is desired, a low caloric bulking agent can beused. Example of low caloric bulking agents include: polydextrose;Raftilose, Raftilin; Fructooligosaccharides (NutraFlora); Palatinoseoligosaccharide; Guar Gum Hydrolysate (Sun Fiber); or indigestibledextrin (Fibersol). However, other low calorie bulking agents can beused.

A variety of flavoring agents can be used. The flavor can be used inamounts of approximately 0.1 to about 15 weight percent of the gum, andpreferably, about 0.2 to about 5%. Flavoring agents may includeessential oils, synthetic flavors or mixtures thereof including, but notlimited to, oils derived from plants and fruits such as citrus oils,fruit essences, peppermint oil, spearmint oil, other mint oils, cloveoil, oil of wintergreen, anise and the like. Artificial flavoring agentsand components may also be used. Natural and artificial flavoring agentsmay be combined in any sensorially acceptable fashion.

The present invention, it is believed, can be used with a variety ofprocesses for manufacturing chewing gum.

Chewing gum is generally manufactured by sequentially adding the variouschewing gum ingredients to commercially available mixers known in theart. After the ingredients have been thoroughly mixed, the chewing gummass is discharged from the mixer and shaped into the desired form, suchas by rolling into sheets and cutting into sticks, extruding intochunks, or casting into pellets.

Generally, the ingredients are mixed by first melting the gum base andadding it to the running mixer. The gum base may alternatively be meltedin the mixer. Color and emulsifiers can be added at this time.

A chewing gum softener such as glycerin can be added next along withpart of the bulk portion. Further parts of the bulk portion may then beadded to the mixer. Flavoring agents are typically added with the finalpart of the bulk portion. The entire mixing process typically takes fromfive to fifteen minutes, although longer mixing times are sometimesrequired.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope of the present invention andwithout diminishing its attendant advantages. It is therefore intendedthat such changes and modifications be covered by the appended claims.

We claim:
 1. A gum base including at least one polyester that isproduced through a reaction of glycerol and at least one acid chosenfrom the group consisting of citric acid, fumaric acid, adipic acid,malic acid, succinic acid, suberic acid, sebacic acid, dodecanedioicacid, glucaric acid, glutamic acid, glutaric acid, azelaic acid, andtartaric acid.
 2. The gum base of claim 1 wherein the base is wax-free.3. The gum base of claim 1 wherein the base is non-tacky.
 4. The gumbase of claim 1 wherein the base is a bubble gum-type base.
 5. The gumbase of claim 1 wherein the polyester comprises approximately 1% toabout 80% by weight of the base.
 6. The gum base of claim 1 including atleast one elastomer.
 7. A gum base including at least approximately 1%by weight of a polyester that is a product of a reaction of trihydroxylalcohol and one acid chosen from the group consisting of dicarboxylicacid and tricarboxylic acid.
 8. The gum base of claim 7 wherein the baseis wax-free.
 9. The gum base of claim 7 wherein the base is non-tacky.10. The gum base of claim 7 wherein the base is a bubble gum-type base.11. The gum base of claim 7 wherein the polyester is produced by thereaction of glycerol and at least one acid chosen from the groupconsisting of citric acid, fumaric acid, adipic acid, malic acid,succinic acid, suberic acid, sebacic acid, dodecanedioic acid, glucaricacid, glutamic acid, glutaric acid, azelaic acid, and tartaric acid. 12.The gum base of claim 7 including at least one elastomer.
 13. A chewinggum formulation comprising:an insoluble gum base; a water solubleportion; a flavor; and at least 0.1% by weight of a polyester producedby the reaction of glycerol and at least one acid chosen from the groupconsisting of citric acid, fumaric acid, adipic acid, malic acid,succinic acid, suberic acid, sebacic acid, dodecanedioic acid, glucaricacid, glutamic acid, glutaric acid, azelaic acid, and tartaric acid. 14.The chewing gum formulation of claim 13 wherein the formulation includesa bulk sweetener.
 15. The chewing gum formulation of claim 13 whereinthe formulation includes a high intensity sweetener.
 16. The chewing gumformulation of claim 13 wherein the formulation includes an elastomerplasticizer.
 17. The chewing gum formulation of claim 13 wherein theformulation includes an elastomer.
 18. The chewing gum of claim 13wherein the chewing gum is sugar free.
 19. A method for manufacturingchewing gum comprising the step of adding to a water soluble portion anda flavor an edible polyester produced by the reaction of trihydroxylalcohol and at least one acid chosen from the group consisting ofdicarboxylic acid and tricarboxylic acid.
 20. The method of claim 19including the step of adding at least one elastomer to the water solubleportion, flavor, and edible polyester.